Buggy code:
this . parent = parent ; tabFolder = new CTabFolder ( parent , ( ( SWT . BORDER ) | ( EditorWorkbook . tabLocation ) ) ) ; tabFolderListener = new IPropertyChangeListener ( ) { public void propertyChange ( PropertyChangeEvent event ) { if ( event . getProperty ( ) . equals ( EDITOR_TAB_WIDTH_SCALAR ) ) { tabFolder . MIN_TAB_WIDTH = getPreferenceStore ( ) . getInt ( EDITOR_TAB_WIDTH_SCALAR ) ; if ( getPreferenceStore ( ) . getBoolean ( EDITOR_LIST_PULLDOWN_ACTIVE ) ) { tabFolder . setTopRight ( pullDownBar ) ; pullDownBar . setVisible ( ( ( tabFolder . getItemCount ( ) ) >= 1 ) ) ; } else { pullDownBar . setVisible ( false ) ; tabFolder . setTopRight ( null ) ; } } if ( event . getProperty ( ) . equals ( EDITOR_LIST_PULLDOWN_ACTIVE ) ) { if ( getPreferenceStore ( ) . getBoolean ( EDITOR_LIST_PULLDOWN_ACTIVE ) ) { tabFolder . setTopRight ( pullDownBar ) ; pullDownBar . setVisible ( ( ( tabFolder . getItemCount ( ) ) >= 1 ) ) ; } else { pullDownBar . setVisible ( false ) ; tabFolder . setTopRight ( null ) ; } } } } ; IPreferenceStore store = WorkbenchPlugin . getDefault ( ) . getPreferenceStore ( ) ; store . addPropertyChangeListener ( tabFolderListener ) ; tabFolder . setTabList ( new Control [ 0 ] ) ; tabFolder . setData ( ( ( IPartDropTarget ) ( this ) ) ) ; tabFolder . addCTabFolderListener ( new CTabFolderAdapter ( ) { public void itemClosed ( CTabFolderEvent e ) { e . doit = false ; EditorPane pane = ( ( EditorPane ) ( mapTabToEditor . get ( e . item ) ) ) ; pane . doHide ( ) ; } } ) ; tabFolder . addSelectionListener ( new SelectionAdapter ( ) { public void widgetSelected ( SelectionEvent e ) { if ( handleTabSelection ) { EditorPane pane = ( ( EditorPane ) ( mapTabToEditor . get ( e . item ) ) ) ; if ( pane != null ) { setVisibleEditor ( pane ) ; if ( assignFocusOnSelection ) { ignoreTabFocusHide = true ; pane . setFocus ( ) ; ignoreTabFocusHide = false ; } } } } } ) ; tabFolder . addListener ( Resize , new Listener ( ) { public void handleEvent ( Event e ) { setControlSize ( ) ; } } ) ; tabFolder . addMouseListener ( new MouseAdapter ( ) { public void mouseDoubleClick ( MouseEvent event ) { doZoom ( ) ; } public void mouseDown ( MouseEvent e ) { if ( ( visibleEditor ) != null ) { CTabItem item = getTab ( visibleEditor ) ; if ( ( ( e . stateMask ) & ( SWT . CTRL ) ) != 0 ) { EditorPane pane = ( ( EditorPane ) ( mapTabToEditor . get ( item ) ) ) ; pane . doHide ( ) ; item . dispose ( ) ; } else { visibleEditor . setFocus ( ) ; Rectangle bounds = item . getBounds ( ) ; if ( bounds . contains ( e . x , e . y ) ) { if ( ( e . button ) == 3 ) visibleEditor . showPaneMenu ( tabFolder , new Point ( e . x , e . y ) ) ; else if ( ( ( e . button ) == 1 ) && ( overImage ( item , e . x ) ) ) visibleEditor . showPaneMenu ( ) ; } } } } } ) ; if ( ( ! ( mouseDownListenerAdded ) ) && ( ( getEditorArea ( ) ) != null ) ) { tabFolder . addListener ( MouseDown , getEditorArea ( ) . getMouseDownListener ( ) ) ; mouseDownListenerAdded = true ; } enableDrop ( this ) ; editorList = new EditorList ( getEditorArea ( ) . getWorkbenchWindow ( ) , this ) ; pullDownBar = new ToolBar ( tabFolder , SWT . FLAT ) ; pullDownButton = new ToolItem ( pullDownBar , SWT . PUSH ) ; Image pullDownButtonImage = WorkbenchImages . getImage ( IMG_LCL_VIEW_MENU ) ; pullDownButton . setDisabledImage ( pullDownButtonImage ) ; pullDownButton . setImage ( pullDownButtonImage ) ; <START_BUG> pullDownButton . setToolTipText ( WorkbenchMessages . getString ( "Editors" ) ) ; <END_BUG> pullDownButton . addSelectionListener ( new SelectionListener ( ) { public void widgetSelected ( SelectionEvent e ) { openEditorList ( ) ; } public void widgetDefaultSelected ( SelectionEvent e ) { } } ) ; if ( store . getBoolean ( EDITOR_LIST_PULLDOWN_ACTIVE ) ) { tabFolder . setTopRight ( pullDownBar ) ; pullDownBar . setVisible ( true ) ; } else { pullDownBar . setVisible ( false ) ; tabFolder . setTopRight ( null ) ; } tabFolder . MIN_TAB_WIDTH = store . getInt ( EDITOR_TAB_WIDTH_SCALAR ) ; Iterator = editors . iterator ( ) ; } private void closeEditorList ( ) { } public void openEditorList ( ) { } private void setEditorListBounds ( Shell parent ) { } public void resizeEditorList ( ) { } public void showPaneMenu ( ) { } boolean overImage ( EditorPane pane , int x ) { } private boolean overImage ( CTabItem item , int x ) { } private void createPage ( EditorPane editorPane ) { } private CTabItem createTab ( EditorPane editorPane ) { } private CTabItem createTab ( EditorPane editorPane , int index ) { } private void disableTabDrag ( LayoutPart part ) { } public void dispose ( ) { } private void doZoom ( ) { } void drawGradient ( ) { } private void enableDrop ( LayoutPart part ) { } private void enableTabDrag ( LayoutPart part , CTabItem tab ) { } public Rectangle getBounds ( ) { } public int getMinimumHeight ( ) { } public LayoutPart [ ] getChildren ( ) { } public Control getControl ( ) { } public EditorArea getEditorArea ( ) { } public int getItemCount ( ) { }

Fix:
pullDownButton . setToolTipText ( WorkbenchMessages . getString ( "EditorList.button.toolTip" ) ) ;